1. Field of the Invention
The present invention is related to a touch control system, and particularly to a touch control system with multi-touch detection functions.
2. Description of the Prior Art
Please refer to FIG. 1. FIG. 1 is a diagram illustrating a method of a self-capacitance touch panel detecting at least one touch point. The method of the self-capacitance touch panel detecting the at least one touch point utilizes voltage scanning signals provided by a driving circuit to scan N sensing lines in turns in an X direction of a touch panel, and then to scan M sensing lines in turns in a Y direction of a touch panel, or utilizes the voltage scanning signals to scan the M sensing lines in turns in the Y direction of the touch panel, and then to scan the N sensing lines in turns in the X direction of the touch panel. A capacitance of a sensing line increases when the sensing line is touched by at least one object, so the sensing line touched by the object can be detected according to a change of a duty cycle of the voltage scanning signal. But, the self-capacitance touch panel may misjudge some touch points when the self-capacitance touch panel is touched by a plurality of touch points. Please refer to FIG. 2. FIG. 2 is a diagram illustrating the self-capacitance touch panel generating a ghost point. As shown in FIG. 2, the self-capacitance touch panel can detect coordinates of both points A, B by scanning the M sensing lines in the Y direction of the touch panel and the N sensing lines in the X direction of the touch panel when two objects touch the points A, B of the touch panel. But, the self-capacitance touch panel can also further detect both coordinates of points A′, B′, so the points A′, B′ of the touch panel are ghost points.
Please refer to FIG. 3. FIG. 3 is a diagram illustrating a method of a mutual capacitance touch panel detecting at least one touch point. The mutual capacitance touch panel can detect positions of a plurality of touch points accurately. The method of the mutual capacitance touch panel detecting the touch points is utilizing voltage scanning signals or current scanning signals to scan sensing lines in turns in an X direction (or a Y direction) of the mutual capacitance touch panel, and then to capture feedback signals from all sensing lines in the Y direction (or the X direction) of the mutual capacitance touch panel. But, a large amount of data is generated by the method of the mutual capacitance touch panel detecting the at least one touch point, and the data must be processed to generate the true touch points. Therefore, the mutual capacitance touch panel can accurately detect the positions of the plurality of touch points, but the mutual capacitance touch panel not only requires massive storage, but also heavy data processing.